Engraving-machine.



PATENTED JUNE so, 1903.

R. TRENTZSGH. ENGRAVING MACHINE.

APPLIOATION FILED MAB. 6, 1903.

N0 MODEL.

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No. 732,4'72. Patented June 30, 1903".

UNITED STATES PATENT OFFICE.

ROBERT TRENTZSqI-I, OF LEIPZIG, GERMANY, ASSIGNOR TO THE FIRM OF ELEKTROGRAVURE GESELLSOHAFT MIT BESCHRANKTER HAFTUNG, OF LEIPZIG, GERMANY.

ENGRAVING-MAC'HIINE.

'QPECIFICATION forming part of Letters Patent No. 732,472, dated June 30, 1903.

I Application filed March 6, 1903. Serial No. 146,434. (No model.)

To all-whom it may concern: f entering a longitudinal groove is of bed- Be it known that I, ROBERT TRENTZsCH,'-a plate is, so that the slide-rest is adjustable subject of the King of Saxony, and a resident upon the bed-plate. Thus by setting the enof Leipzig-Neustadt, Saxony, Germany, have graving-tool d and slide-rest fto the right or invented certain new and useful Improve left the size of the copy produced can be inments in Engraving-Machines, of which the creased or diminished. The mandrelf' carfollowing is a specification. ries a worm-wheel m, by means of which it This invention relates to a machine for enis rotated.

graving reliefs which is so constructed that The leverc is held against the modelz' or 71,

IO friction is avoided, sunk and raised models which is either attached todiskAorto diskA may be copied, and an accurate reproduction by springs Z Z, and is moved in the usual manof the model is obtained. nor by a screw and not or otherwise, so that In the accompanying drawings, Figurel is the tracer is projected radially across the a plan of an engraving-machine embodying model. As the tracer is conducted from the 15 my invention, and Fig. 2 a front elevation center toward the periphery of the model it of the same with some of the parts omitted. describes a small arc, of which the fulcrum The letter it represents the bed-plate of the of lever c is the center, a similar are being machine, to which is connected by upright. simultaneously described by the engravingpivot a a bearing at, having a forwardly-extool upon the work-piece. The model and 20 tending pivot b. This pivot is embraced by work-piece rotate in opposite directions, as the hub c of a lever 0, so that a universal indicated bythe arrowsin Fig. 2. The tracere joint is formed between the bed-plate and therefore arrives at a given point of the model lever. Upon one armof lever c are mounted earlier than the engraving-tool arrives at a a pair oftracers e c, which extend in oppocorresponding point of the work-piece within 25 site directions. If the'machineis in use, only the same parallel circle. If the engraving is one of these tracers-via, either tracer e or to be a true copy of the model, it is necestracer e'is in operation, the selection of the sary that all points of the model-describe the one to be used depending upon the nature of same length of way before'being reached by the model and of the copy desired. If, for the tracer, as the corresponding points of instance, a raised copy is to be made from a the work-piece must describe before being raised model i, the latter is attached to adisk reached by the engraving-tool. If the model A opposite tracer e, so that tracer e is in and the work-piece are of different size, the operation. If, however, a raised copy is to length of way described must be in like manbe made from a sunk model 7 the latter is ner of proportionate size. To illustrate:

5 attached to a disk A opposite tracer e, which The point z otthe model would simultaneis now put in operation. It will be seen that ously describe a complete circle D minus the by this arrangement it is possible to make area I, while the point z of the work-piece raised copies from raised models or raised would describe the circle E plus thearc z d. copies from sunk models, and vice versa. The To avoid this defect, which would produce a 0 disks A A of patternst'z" are secured to mandistortion in the engraving, I so regulate the drels 2' i respectively,'which turn in bearspeed of the model and work-piece that the ings h h. They receive rotary motion by ways described for each given point-thereon worm-wheels m or m in the manner hereinare equal when the modeland work-piece are after described. The engraving-tool d, roof the same size and that the ways are pro- 5 tated'by electric or other power, is adjustportionate when model and work-piece are of 5 ably mounted upon the other arm of lever c .difierent size. The means for carrying out and engages the work-piece g, which is mountthis result are as follows: The lever c carries ed upon a disk B, attached to a mandrel f, at its rightend an arm 0 passing througha that turns in suitable bearings of a slide-rest perforated sleeve 0. This sleeve carries a 50 f. This slide-rest is provided with set-screws pin o ,which is adapted to slide within a sleeve 10o of a slide 0, guided in suitable manner within the frame of the machine. A tapped perforation of slide 0 is engaged by a screw-shaft 0, that receives motion from counter-shaft r by stepped pulley r belt r stepped pulley o Worm 0 and worm-wheel 0 fast on shaft 0. The shaft 0 rotates by bevel-gear u u, the shaft 1' of a Worm s. This worm engages a worm-wheel fast on shaft w, which carries also two eccentrics y. Against each eccentric is held by spring Z a roller ac, hung in the lower arm of a lever q, fulcrumed at w. The upper arm of each lever q is by link q connected to a sliding bearing y, through which passes the'hnb of a tubular worm s, which is taken along by the bearing by means of collars 8 One worm s engages worm-wheel m of mandrel 11 and is slidable upon one end of counter-shaft 1', while the other worm 8 engages worm-wheel m of mandrel 2' and is slidable upon a shaft 1". Both worms participate in the rotation of their respective shafts by feather-and-groove connections. Countershaft 0' receives motion from power-pulley r by gear-wheels 1' 7, While shaft 7" receives motion from gear-Wheel 1' by gear-Wheel r shaft 1, and gear-wheels r r. Ihe opposite end of shaft 1 is provided with a worm s", which is fixed thereon and engages the wormwheel on of mandrel f. By the mechanism described the oscillation of lever o'will be accompanied by a simultaneous rotation and advance of the worm s, which will retard the rotation of the model in relation to the rot-ation of the work-piece in such a manner that corresponding points of the model and workpiece will describe the same or proportionate ways.

What I claim is- 1. In an engraving-machine, the combination ofa lever with a pair of tracers projecting therefrom in opposite directions, and with a pair of model-carrying mandrels arranged opposite said tracers, substantially as specified.

2. In an engraving-machine, the combination of a lever with a tracing-tool and an engraving-tool connected thereto, means for tilting thelever, mandrels for carrying the model and work-piece respectively, and means for simultaneously rotating said mandrels in opposite directions at different speeds, substantially as specified.

3. In an engraving-machine, the combination of a lever with a tracing-tool and an engraving-tool connected thereto, a shaft for tilting the lever, a sliding rotatable worm operatively connected to the shaft, a model-carrying mandrel, and a worm-wheel on said mandrel which is engaged by the worm, substantially as specified.

Signed by me at Leipzig, Germany, this 18th day of February, 1903.

ROBERT TRENTZSCI-I.

Witnesses:

RUDOLPH FRICKE, R. P. O. DUNN. 

